The natural colored gemstone and cultured pearl source of information and ideas.

Discusses certification, shapes, grade, and other diamond related topics. Also includes precious metal guides.

Diamond buying guide includes a price database, diamonds tutorial, and diamond FAQ.

Facts about opal include chemical make-up, buying advice, cutting and polishing basics, and opal care. Includes photos of different types of opals.

Offers articles discussing jewelry terminology, pricing, quality measures.

A reference library covering natural gemstones and minerals, synthetic and treated gems. Also offers resources for people who would like to pursue a career in gemology.